Avaliação da expressão da BMP -2/4 e BMPR-IA em Carcinoma Epidermóide Oral metastático e não metastático

The expression of bone morphogenetic proteins (BMPs) is altered in a variety of human canceres. The BMP-2/4 and BMPR-IA were recently shown to be overexpressed in high-risk premalignant and malignant lesions of oral epithelium. The present study analysed the expression of BMP-2/4 and BMPR-IA in Oral Squamous Cell Carcinoma (OSCC) such as their implications in disease prognostic using munohistochemistry. Ten cases of Oral Fibroepithelial Hiperplasia were selected as a control group. The experimental group included 16 cases of OSCC without metastases and 7 cases of OSCC metastatic. The presence or absence of nodal metastases was used as parameter to evaluated the disease prognostic. The results demonstrated weak immunoreactivity for BMP-2/4 and BMPR-IA in every case of the control group. In the cases of OSCC with metastases an overexpression of BMP-2/4 (71,4%) was observed while the BMPR-IA showed weak expression (85,7%). In the cases of OSCC without metastases BMP-2/4 (62,5%) and BMPR-IA showed strong immunostaining standing out an overexpression of the receptor in all the specimens. Observed statistical significance for correlation between the oral cancer prognostic and the staining intensity of the BMP-2/4 (p=0,002). There wasn t statistical significance for association between the staining intensity of the BMPR-IA and the disease prognostic (p<0,001). In conclusion, this findings suggest that the overexpression of BMP-2/4 associated with the loss of expression of the BMPR-IA in OSCC metastatic has prognostic relevance, as the loss of sensitivity to BMPs can be an indicative of metastases development in OSCC

Estudo clínico-patológico do carcinoma epidermóide de língua e imunoistoquímico das proteínas BMP-2, BMPR-IA, BMPR-II e endoglina

Bone morphogenetic proteins (BMPs) are cytokines involved in proliferation and angiogenesis of many kind of human cancer. The present study analyzed the immunohistochemical expression of BMP-2, BMPR-II, BMPR-IA and endoglin (CD105) and their relationship with the biological behavior and local angiogenesis in tongue oral squamous cells carcinoma (SCC). The sample consisted of 25 cases of tongue SCC without metastasis, 25 tongue SCC with metastasis and 25 cases of Inflamatory Fibrous Hyperplasia (IFH).The histological grade of malignancy proposed by Bryne (1998), adapted by Miranda (2002) was used to classify all tongue SCC cases. Score 0 was attributed to absent-weak immunoexpression and score 1 for strong immunostaning and pattern of distribution was focal or diffuse. Microvessel counts (MVC) was established for CD105. Most of the patients with tongue SCC was male. The principal age in tongue SCC without metastasis was over 65 years and in tongue SCC with metastasis was between 45-65 years. There were predominance of stage II in TNM and in the specimens with high-grade, independent of studied group. For BMP-2, 56% of tongue SCC without metastasis and 72% tongue SCC with metastasis exhibited score 1 while the IFH showed secore 0 in 72% of the cases, with statistical association (p=0,007). Considering the BMPR-II, 52% of tongue SCC without metastasis exhibited score 0; 56% tongue SCC with metastasis and 60% IFH showed score 1. The majority cases of BMPR-IA demonstrated score 1 and 100% of CD105 exhibited strong immunoexpression in tongue SCC. Regarding the pattern distribution, it was noted a tendency to diffuse pattern for the proteins in all groups. The means of MVC were similar in tongue SCC without metastasis (32,91) and in tongue SCC with metastasis (32,05), however existed statistical difference with IFH (p<0,001). There was statistical association of BMP-2 expression with BMPR-II (p=0,008), BMPR-IA (p=0,006) and CD105 (p=0,046). An association between TNM and BMP-2 immunoexpression and their receptors was not detected, nevertheless this association was found with MVC (p=0,047) whose averages were higher for the stages II (35,97) e IV (35,69). No association between histological grading and these proteins was observed. This study suggests that the superexpression of BMP-2 signaling pathways acts on cell proliferation in tongue SCC and can be implicated with more invasive potential. Additionaly, the CD105 is a potent biological marker of neovascularization in this neoplasm and their association with BMP-2 and BMPR-IA receptor, showed that this type of cancer in BMP-2 is presented as pro-angiogenic in the metastatic process

Avaliação imuno-histoquímica das galectinas-1, -3, -4 e -7 em carcinoma epidermóide de língua.

Several studies are carried out with aim to establish parameters to determine biologic behavior of oral squamous cell carcinoma, in order this neoplasm presents high rates of morbidity and mortality. The purpose of present research was to performe a clinic, morphologic and immunohistochemical analysis by the expression of galectins 1, 3, 4 and 7 in 65 cases of tongue squamous cell carcinoma, correlating this expression with clinics (outcome of the disease, metastasis and clinical staging) and morphologic parameters (malignancy histologic gradation system). The clinical and morphologic parameters analysed and expression of galectins 1, 3, 4 and 7 were submitted to statistical analysis (Qui2 test), observing that can be utilized as indicators of the biological behavior of the tongue squamous cell carcinoma. The galectin 1 was expressed in 87,7% of cases studied and it exhibit statistically significant correlation with metastasis (p=0,033) and clinical staging (p=0,016), it is located mostly in the citoplasm of the stomal cells. The immunoexpression of galectin 3 in 87,7% of cases was correlated with the presence of metastasis (p=0,033) and malignancy histological gradation system (p=0,031), observed, mostly of cases, in tongue squamous cell carcinoma of malignancy high grading. The galectin 4 showed no statistical significance to any of the parameters evaluated. The expression of galectin 7 in 73,8% of cases showed statistically significant correlation with the malignancy histologic grading (p=0,005), which is marking exclusively found in neoplastic epithelial cells, in the mostly of cases, it is found in cytoplasm and membrane (50%). The expressive immunopositivy of the galectins 1, 3 and 7, observed in this research, leads us to suggest a broad participation of these proteins in oral carcinogenesis, and its possible use as markers of biological behavior and tumor progression in cases of squamous cell carcinoma of the tongue

Associação entre polimorfismos funcionais nos genes da MMP-7 e MMP-9 e o perfil clinicopatológico do carcinoma epidermóide de língua

Matrix metalloproteinase-7 (MMP-7) and -9 (MMP-9) modulate important functions strictly related to the development, invasion and metastasis of several human cancers among them the squamous cell carcinoma of the tongue (SCCT). However, individual genetic factors such as the functional single nucleotide polymorphisms (SNPs) influence the pattern of protein expression of these MMPs and thus may be related to the variability observed in the clinical behavior of patients with SCCT. In this context, the present cross-sectional study aimed to evaluate the association between the frequency of the functional SNPs MMP-7 -181 A/G and MMP-9 -1562 C/T and the clinical (age, gender and metastasis) and pathological (malignancy histological grading and immunohistochemistry expression) features of SCCT cases. Genotyping of these SNPs were performed by PCR-RFLP on DNA samples from 71 cases of SCCT and 60 individuals without cancer who constitute the control group. Among the results of this research, it was observed that the frequency of the polymorphic alleles MMP-7 -181 G and MMP-9 -1562 T in SCCT patients was 28% and 12%, respectively, and the frequency of the heterozygotes A/G (PR = 2.00; p < 0.001) and C/T (PR = 1.54; p = 0.014) were significantly higher in the patient group than in the controls. The prevalence of patients carrying the combination of SNPs studied was significantly associated with SCCT cases (PR = 2.00; p = 0.011) and metastasis (PR = 2.00; p < 0.001). Furthermore, with the frequency of SNPs analyzed, the age, gender, histological grading and immunoreactivity of MMP-7 and MMP-9 formed clinical and pathological parameters relevant to the identification of population subgroups more related to the development of SCCT and metastasis. Based on these results, it is suggested that the protein expression levels of MMP-7 and -9 substantially influence the balance between their pro- and anticancer biological functions and hence the clinicopathological profile of the squamous cell carcinoma of the tongue

Estudo da expressão imuno-histoquímica das MMPs -2, -7, -9 e -26 e TIMPs -1 e -2 em adenomas pleomórficos e carcinomas adenóides císticos de glândulas salivares menores

The balance between the expression of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) has been related to various physiological and pathological processes, including salivary gland morphogenesis and tumor invasion and metastasis processes. Pleomorphic adenoma (PA) and adenoid cystic carcinoma (ACC) respectively represent benign and malignant neoplasias of salivary glands. Although they share the same cell origin, they present distinct biological behavior. The aim of this study was to compare the immunohistochemical expression of MMPs -2, -7, -9 and -26, and of TIMPs -1 and -2, in cases of PA and ACC of minor salivary glands. Twenty cases of PA and twenty cases of ACC were assessed according to the presence, intensity and location of MMPs and TIMPs in the tumor parenchyma. Most of the PAs and ACCs presented a high expression of MMP -2, -7, -9 and -26 and of TIMP -1 and -2, predominantly located in tumor cells. There was no significant difference in the expression of MMPs -2 (p=0.359), -7 (p=0.081) and -26 (p=0.553), as well as of TIMPs -1 (p=0.657) and -2 (p=0.248), between the parenchyma of PAs and ACCs. However, MMP-9 showed a significant difference of expression between the two tumors, with the ACC showing more intense marking for this gelatinase (p=0.041). The strong expression of MMP-9 observed in the parenchyma suggests that this gelatinase may play an important role in the biological behavior of these tumors. On the other hand, although there was no significant difference between the marking of MMP -2, 7 and 26 in the studied tumors, the data, when analyzed as a whole, suggest that these proteases may take part in the process of tissue remodeling in both tumors, but do not present a direct relation with the pattern of aggressiveness of ACC. Nonetheless, matrilisins may indirectly influence the behavior of this tumor due to their capacity of activating MMP-9, strongly expressed in the parenchyma of ACC

Avaliação da expressão imuno-histoquímica de marcadores de hipóxia em carcinoma epidermóide de língua

The tumor hypoxia modulates a series of genetic changes related to adaptive development, invasion and metastasis of various human cancers, among which squamous cell carcinoma of the tongue (SCCT). The objective of this study was to analyze clinical, morphological and immunohistochemical expression by HIF-1α, GLUT-1 and CA-IX in 57 cases of CEL and correlated this expression to clinical parameters and morphological. After a descriptive analysis of data on gender, age, race, and habits of patients, it was found that the results were consistent with the literature. The clinical and morphological parameters analyzed and the expression of these markers of hypoxia were subjected to statistical analysis (Qui2 test), verifying that they can be used as indicators of the biological behavior of CEL. Among the results of this study, we observed that the intensity of expression for HIF-1α, in most cases located in the cytoplasm and nucleus, statistically correlated with clinical staging (p = 0.011) and histological grading (p = 0.002). As for the relationship between the distribution of labeling for HIF-1α and metastasis, the chi-square (Qui2) showed that there was statistically significant differences between the groups (p = 0.040). 75.8% of the sample who had metastases, there was the predominance of diffuse marking. The immunoexpression cytoplasmic/membrane GLUT-1 showed a statistically significant correlation with the clinical stage (p = 0.002) and histological grading (p = 0.000). Concerning the location of markings for GLUT-1 tumor on the island, there was a predominance of peripheral marking specimens in most low-grade (78.6%). In the sample of high-grade, prevailed the location center/periphery (55.8%). According to the chi-square (Qui2), the location on the island of the tumor (p = 0.025) showed statistically significant difference in histological grading. The immunoreactivity of CA-IX, in most cases located in the membrane and cytoplasm, exhibited a statistically significant correlation with histological grading (p = 0.005). Based on these results, we can conclude a broad participation of these markers of hypoxia in oral carcinogenesis and its possible use as markers of biological behavior and tumor progression in CEL

Imunoexpressão de vegf-c, vegfr-3 e hif-1α e mensuração da densidade linfática em carcinomas epidermóides de lábio inferior metastáticos e não-metastáticos: uma relação com parâmetros clinicopatológicos e prognósticos

Squamous cell carcinoma of the lower lip is among the most common malignant tumors of the oral and maxillofacial region, with good prognosis in more than 90% of patients with 5-year survival. In these carcinomas, the development of lymph node metastasis decreases the prognosis and it has been associated with the formation of new lymphatic vessels. It has been suggested the important role of vascular endothelial growth factor-C (VEGF-C), the receptor type 3 VEGF (VEGFR-3) and hypoxia-induced factor 1 (HIF-1) in this process. The aim of this study was to evaluate the immunoexpression of VEGF-C, VEGFR-3 and HIF-1α and correlate with intra and peritumoral lymphatic density in squamous cell carcinomas of the lower lip metastatic and non-metastatic. The sample consisted of 50 cases of squamous cell carcinoma of lower lip, of which 25 had regional lymph node metastasis and 25, absence of metastasis. The percentages of cells immunostained for VEGF-C, VEGFR-3 and HIF-1α in front of tumor invasion and in the center of tumor were evaluated. Microvessel density lymphatic (MDL) was determined by the counting of lymph microvessels immunostained by the anti-D2-40 in five fields (200×), in an area of evaluation with 0.7386 mm2. The invasion of the lymph vessels by malignant cells was also evaluated. Immunostaining was correlated with the presence and absence of metastasis, TNM clinical stage, local recurrence, disease outcome (remission of injury or patient death) and histological grading. The analysis of intra and peritumoral lymphatic density showed no significant association with clinicopathological parameters and immunoexpressions of VEGF-C, VEGFR-3 and HIF-1α (p > 0,05). There was a weak positive correlation, significant, between intra and peritumoral lymphatic density (r = 0,405; p = 0,004). VEGF-C showed no significant association with clinicopathological and prognosis parameters (p > 0,05). For VEGFR-3, there was scarce membrane staining and intense and homogenous cytoplasmic staining in neoplastic cells. Percentage of positive cytoplasmic VEGFR-3 in center of tumor, exhibited a statistically significant association with metastasis (p = 0,009), patient death (p = 0,008) and histological grades of malignancy proposed by Bryne et al. (1992) (p = 0,002) and World Health Organization (p = 0,003). A low positive correlation was statistically significant between the immunoreactivity of VEGFC and VEGFR-3 cytoplasmic (r = 0,358; p = 0,011) and between the percentage of positive cytoplasmic VEGFR-3 in front of tumor invasion and in the center of the tumor (r = 0,387; p = 0,005) was also demonstrated. There was no association between HIF-1α, clinicopathological and prognosis parameters, and VEGF-C and VEGFR-3. The percentage of nuclear positivity for HIF-1α was significantly higher in cases without invasion of peritumoral lymphatic (p = 0,040). Based on the results we can conclude that most cytoplasmic expression of VEGFR-3 in center of tumor in metastatic cases, high degree of malignancy and poorly differentiated, contributes to poor outcome of squamous cell carcinoma of the lower lip, including patient death. Intra and peritumoral lymphatic density seems to be not associated with lymph node metastasis in these carcinomas

Avaliacao de polimorfismos nos genes XPD e XRCC3 em carcinomas orais de celulas escamosas

Oral squamous cell carcinoma (OSCC) is an important cause of morbidity and mortality worldwide despite recent advances in treatment. There are several studies aiming to find markers that may improve the assessment of this disease prognosis. Studies about genetic polymorphisms have gained prominence due to their influence on individual susceptibility to cancer development. The aim of this study was to evaluate the association between the frequency of polymorphisms XPD Lys751Gln and XRCC3 Thr241Met and clinicopathological features of OSCC cases, including age, sex, presence or absence of metastases, and histological grading of malignancy according to Bryne (1998). Sample consisted of 54 cases of OSCC and 40 cases of inflammatory fibrous hyperplasia (IFH). OSCC cases were classified as low or high grade. DNA samples were previously extracted from paraffin blocks. Genotypes for each case were determined through PCR-RFLP (polymerase chain reaction - restriction fragment length polymorphism). Results were analyzed by Fisher s exact test and Chi-square test and the odds ratio was calculated considering p < 0.05 to indicate statistical significance. For XPD, Lys/Gln genotype was more common in IFHs (n=28; 70%) than in OSCCs (n=24; 44.4%) (OR: 0.3; p<0.05). Frequency of Gln allele was higher in high-grade lesions when compared to low grade lesions (0.48 and 0.21, respectively) (OR: 3.4; p<0.05). For XRCC3, Met allele was more common in OSCC than in IFH (0.49 and 0.35, respectively) (OR: 2.6; p<0.05). Met/Met genotype was associated with presence of metastases (OR: 8.1; p<0.05). There was no statistically significant association between the genotypes and the age or sex of patients. In the present sample, the higher frequency of XPD Gln allele in IFH reveals a possible protective role of this variant against the development of OSCC. However, its association with high-grade lesions indicates that this allele could influence the tumor progression after the neoplasia development. The presence of XRCC3 Met allele, in turn, seems to contribute to the development of OSCC and metastases

Expressão imuno-histoquimica de proteínas relacionadas com a reabsorção óssea em carcinoma epidermoide de palato duro e língua

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Expressão imuno-histoquímica da e-caderina e do CD44v6 em carcinoma epidermóide de lábio inferior e língua

The objective of this study was perform, by the streptoavidin-biotin technique, an immunohistochemical analysis of the E-cadherin and CD44v6 in 15 lower lip squamous cell carcinomas and 15 of tongue, with varied histologic gradation of malignidade, in order to establish a possible relation between the expression these proteins and the anatomical localization of the lesions, metastasis, as well as with the Bryne`s histolologic grading of malignancy system. It was not observed significant statistical association between the localization of the lesions and the malignancy score, however, had a significant correlation between the histologic parameters of malignancy gradation and the total score of malignancy, being that the parameter degree of keratinization presented the highest correlation (r = 0,844). Taking in consideration the anatomical localization of the lesions, it was not significant difference between the profile of expression and the amount of immunopositive cells for Ecaderina and CD44v6. To the metastasis variable, also it was not observed significant difference between the profile of expression and the amount of immunopositive cells for evaluated proteins. However, it was observed a statistical significant difference in relation to the scores of malignancy, being that the low score presented the highest values for the profile of expression and the amount of immunopositive cells for the E-caderina and the CD44v6. It was observed a statistically significant and negative correlation between the expression profile, the amount of E-cadherin and CD44v6 immunopositive cells and the total score of malignancy. Therefore, based in the results of this study, it was concluded that the expression of the immunohistochemical markers E-caderina and CD44v6 did not constitute histological indicator of aggressiveness for the patients with lower lip and tongue squamous cell carcinomas

Estudo in vitro dos efeitos da BMP-2 e do seu antagonista Noggin sobre a proliferação e migração celulares em carcinoma epidermóide de língua

Oral squamous cell carcinoma (OSCC) is the most prevalent malignancy in the oral cavity and reach a large number of individuals, has become an important public health problem. Studies have demonstrated changes in pathway components BMP in various types of cancers as prostate, colon, breast, gastric and OSCCs. Is the current knowledge that these proteins may exert pro-tumor effect in more advanced stages of neoplastic development coming to favor progression and invasion tumor. The inhibition of the signaling pathway BMP-2 through its antagonists, have shown positive results of antitumor activity and use of Noggin may be a novel therapeutic target for cancer. Given this evidence and the few studies with BMP-2, Noggin and OSCC, the objective of this research was to evaluate the effect of BMP-2 and its antagonist Noggin on proliferation and migration cell in line of cell cultures of human tongue squamous cell carcinoma (SCC25). The study was divided in three groups, a control group, where SCC25 cells suffered no treatment, a BMP-2 group, in which cells were treated with 100ng/ml of BMP-2 and a group of cells that were treated with 100ng/ml of Noggin. For the proliferation assay and cell cycle were established three time intervals (24, 48 and 72 hours). Proliferative activity was investigated by trypan blue and cell cycle analysis by staining with propidium iodide flow cytometry. The potential for migration / invasion of SCC25 cells was performing by a cell invasion assay using Matrigel in a 48-hour interval. The proliferation curve showed a higher proliferation in cells treated with BMP-2 in 72 hours (p < 0.05), and lower overgrowth and cell viability in Noggin group. Recombinant proteins favored a greater percentage of cells in cell cycle phase Go/G1 with a statistically significant difference in the interval of 24 hours (p < 0.05). BMP- 2 produced a greater invasion of cells studied as well as its antagonist Noggin inhibits invasion of cells (p < 0.05). Thus, these results indicate that BMP-2 promotes malignant phenotype, dues stimulates proliferation and invasion of SCC25 cells and, its antagonist Noggin may be an alternative treatment, due to inhibit the tumor progression

Tireóide ectópica cervical lateral: Relato de caso e revisão da literatura

Tireóide ectópica é qualquer tecido tireoideano localizado fora de sua topografia habitual, podendo apresentar-se na linha mediana do pescoço ou, mais raramente, na região cervical lateral. Algumas teorias tentam explicar a origem do tecido tireoideano ectópico: 1. falha na descida da glândula; 2. seqüestro de nódulos tireoideanos; 3. presença de tecido tireoideano na cápsula de linfonodos cervicais; 4. formação teratomatosa; 5. Secundário a anomalias branquiais. Na abordagem diagnóstica, diversos exames têm sido utilizados, sendo o diagnóstico definitivo algumas vezes fornecido apenas pelo estudo histopatológico. Apesar das controvérsias em relação às abordagens terapêuticas apresentadas na literatura, é necessário um planejamento rigoroso para evitar iatrogenias. Conclui-se que a presença de tecido tireoideano ectópico deve ser lembrada no diagnóstico diferencial de massas cervicais laterais, e sua origem histológica considerada, sendo na maioria das vezes metástase de um carcinoma tireoideano oculto. Os autores relatam um caso de tecido tireoideano ectópico lateral no pescoço, em paciente do sexo feminino com bócio colóide mergulhante. Foram realizadas considerações importantes sobre dismorfogênese tireoideana, métodos diagnósticos e opções de tratamento, com revisão da literatura das últimas cinco décadas.

Actinic cheilitis and squamous cell carcinoma of the lip: clinical, histopathological and immunogenetic aspects

Queilite actínica é a principal lesão pré-neoplásica do lábio. O carcinoma espinocelular do lábio é incluído nas estatísticas brasileiras junto com os cânceres de boca e, em conjunto, somam 40% dos cânceres de cabeça e pescoço. Há certo desconhecimento médico e odontológico em geral quanto aos fatores relacionados à carcinogênese e à progressão de tumores de boca. Genes de supressão tumoral e proteínas regulatórias de proliferação celular exercem papel na evolução da queilite actínica para carcinoma espinocelular e no comportamento biológico deste. O conhecimento de marcadores de diagnóstico e prognóstico e sua investigação têm utilidade no acompanhamento de tais pacientes.

Carcinoma de Meibômio como segundo tumor em portadores de retinobastoma: relato de dois casos

O retinoblastoma pode acometer um ou os dois olhos, ocorrendo de forma hereditária ou esporádica. O portador dessa doença pode desenvolver, a longo prazo, outros tipos de tumores não oculares. Relatamos dois pacientes: o filho, portador de cavidade anoftálmica bilateral após remoção dos olhos devido ao retinoblastoma, que apresentou segundo tumor palpebral unilateral, afetando a pálpebra superior; e o pai, portador de cavidade anoftálmica unilateral também por remoção de retinoblastoma e que apresentou tumoração de crescimento rápido na pálpebra superior ipsilateral ao olho enucleado. O exame imuno-histoquímico de ambas as lesões excisadas revelou que se tratava de carcinoma de glândulas sebáceas. Os pacientes evoluíram bem após a remoção do tumor palpebral e, até o momento, não apresentam sinais de recidiva ou metástase.

Methylation status of CDH1 gene in samples of gastric mucous from brazilian patients with chronic gastritis infected by Helicobacter pylori

CONTEXTO:O câncer gástrico é uma das principais neoplasias que causam o óbito no Brasil e no mundo. Helicobacter pylori é um carcinógeno do tipo I relacionado à gastrite crônica. Diferenças no grau de virulência de suas cepas levam a maior risco de desenvolvimento de doenças gástricas. A metilação de ilhas CpGs está envolvida com o processo de tumorigênese em diferentes tipos de câncer. CDH1 é um gene supressor tumoral que, quando inativado, pode aumentar as chances de metástase. A metilação deste gene em estágios precoces da carcinogênese gástrica ainda não é totalmente compreendida. OBJETIVO: Investigar o padrão de metilação do gene CDH1 em amostras de gastrites crônicas e correlacionar com a presença do H. pylori. MÉTODOS: Foram usadas 60 biopsias de mucosas gástricas. A detecção de H. pylori foi realizada por PCR para o gene da urease C e a genotipagem com PCR para os genes cagA e vacA (região s e m). O padrão de metilação do gene CDH1 foi analisado usando a técnica de PCR e específica para a metilação e sequenciamento direto dos produtos de PCR. RESULTADOS: A bactéria H. pylori foi detectada em 90% das amostras de gastrites crônicas; destas, 33% portavam o gene cagA e 100% vacA s1. O genótipo vacA s2/m1 não foi detectado nas amostras analisadas. Metilação de CDH1 foi detectada em 63,3% das amostras de gastrites e 95% delas eram portadoras de H. pylori. CONCLUSÃO: Os resultados deste estudo sugerem que a metilação em CDH1 e a infecção pelo H. pylori são eventos frequentes em amostras de pacientes brasileiros com gastrite crônica e reforça a correlação entre infecção por H. pylori e inativação do gene CDH1 em estágios precoces da tumorigênese gástrica.